GEOPR

This function evaluates the discrete geometric probability density function.

Function Return Value

GEOPR — Function value, the probability that a random variable from a geometric distribution having parameter PIN will be equal to IX. (Output)

Required Arguments

IX — Argument for which the discrete geometric probability density function is to be evaluated. IX must be greater than or equal to 0. (Input)

PIN — Probability parameter of the geometric probability function (the probability of success for each independent trial). PIN must be in the open interval (0, 1). (Input)

FORTRAN 90 Interface

Generic: GEOPR (IX, PIN)

Specific: The specific interface names are S_GEOPR and D_GEOPR.

FORTRAN 77 Interface

Single: GEOPR (IX, PIN)

Double: The double precision name is DGEOPR.

Description

The function GEOPR evaluates the discrete geometric probability density function, defined

 

where p = PIN.

Example

In this example, we evaluate the probability density function at IX = 3, PIN = 0.25.

 

USE UMACH_INT

USE GEOPR_INT

IMPLICIT NONE

INTEGER NOUT, IX

REAL PIN, PR

CALL UMACH(2, NOUT)

IX = 3

PIN = 0.25e0

PR = GEOPR(IX, PIN)

WRITE (NOUT, 99999) IX, PIN, PR

99999 FORMAT (' GEOPR(', I2, ', ', F4.2, ') = ', F6.4)

END

Output

 

GEOPR( 3, 0.25) = 0.1055